Film mirror laminate and mirror member

Abstract

The present invention provides a mirror member which can be easily configured in a complex curved surface shape or the like with good productivity and is excellent in mirror surface properties. The present invention relates to a film mirror laminate having an adhesive layer, a substrate film, a metal reflective layer, and an optical adjustment layer in the stated order, wherein, when light is incident from the optical adjustment layer side at an incident angle of 60° on a sample in which the adhesive layer-side surface of the film mirror laminate is attached to a glass plate, the reflection image clarity at an optical comb width of 0.125 mm is 60% or more.

Description

Film mirror laminate and mirror member

[0001] The present invention relates to a film mirror laminate and a mirror member.

[0002] A vehicle driver drives while gazing forward through the windshield and visually checking the instruments on the instrument panel. In other words, their line of sight moves between the front and the instruments below. If they could see the instruments while keeping their eyes on the front, they would not have to move their eyes, and this is expected to improve drivability (and ultimately safety). Based on this knowledge, head-up display devices have been developed and are now being put into practical use.

[0003] In a head-up display device, an image from a light source is projected as a virtual image onto the windshield within the dashboard device, allowing the driver to view the image. In order to project the image information from the light source without distortion, a mirrored surface with high specularity is required. Furthermore, in order to project the image information from the light source without reducing its brightness, a mirrored surface with high visible light reflectance is required. From the perspective of improving driving safety, head-up displays, which require minimal eye movement, are gaining increasing attention day by day, and the demand for mirrored surfaces used as reflectors is also increasing. Furthermore, due to their low risk of breakage in accidents such as vehicle collisions and their light weight, plastic substrates, particularly polycarbonate substrates due to their high heat resistance, are used as the supporting substrate for the mirrored surface.

[0004] Conventional methods for manufacturing mirror-finished products typically involve forming a metal thin film on a support substrate, such as a polycarbonate substrate, using a batch-type vapor deposition / sputtering device (see, for example, Patent Document 1). However, batch-type manufacturing methods have low production efficiency, and despite the increasing demand for mirror-finished products, there is a problem of supply shortages. Therefore, there is a demand for mirror-finished products that can be manufactured with high productivity. In addition, mirror-finished products are required to have high reflectivity and minimize distortion of reflected light.

[0005] Therefore, a method for manufacturing a reflective mirror using a reflective film that can be attached to a support has been studied. For example, Patent Document 2 discloses that a reflective mirror including a substrate and a reflective sheet on which a reflective film is formed is manufactured by insert molding. Insert molding allows the reflective sheet to be molded integrally with the substrate, which allows for high productivity.

[0006] Japanese Patent Publication No. 2009-265287 Japanese Patent Publication No. 2019-28422

[0007] As described above, in order to project image information from a light source without distortion, the mirror body needs to have high specularity. However, with conventional techniques, it has been difficult to achieve sufficient specularity.

[0008] The present invention was completed in view of the above, and its objective is to provide a mirror member with excellent specularity, and a film mirror laminate that is highly productive, can be easily adapted to complex curved surface shapes, and can provide a mirror member with excellent specularity.

[0009] As a result of extensive research, the inventors have discovered that by setting the reflection clarity of the mirror element in which the adhesive layer side of the film mirror laminate is attached to a supporting substrate within a specific range, it is possible to attach the film mirror laminate to supporting substrates with complex shapes that were difficult to manufacture using conventional batch processing, and thereby produce mirror elements with excellent specularity with high productivity, thereby solving the above-mentioned problem.

[0010] That is, the present invention is as follows. [1] A film mirror laminate having a pressure-sensitive adhesive layer, a base film, a metal reflective layer, and an optical adjustment layer in this order, wherein a sample of the film mirror laminate, in which the surface of the pressure-sensitive adhesive layer side of the film mirror laminate is attached to a glass plate, has a reflection image clarity of 60% or more at an optical comb width of 0.125 mm when light is incident from the optical adjustment layer side at an incident angle of 60°. [2] The film mirror laminate according to [1], wherein the optical adjustment layer comprises a low refractive index layer and a high refractive index layer. [3] The film mirror laminate according to [2], wherein the low refractive index layer contains silicon oxide. [4] The film mirror laminate according to [2], wherein the high refractive index layer contains niobium oxide. [5] The film mirror laminate according to [1], wherein the metal reflective layer contains at least one metal selected from aluminum (Al), zinc (Zn), lead (Pb), copper (Cu), and silver (Ag), or an alloy containing the metal as a main component. [6] A mirror member comprising the film mirror laminate according to any one of [1] to [5] and a supporting substrate, wherein the surface of the film mirror laminate facing the pressure-sensitive adhesive layer is attached to the supporting substrate.

[0011] The film mirror laminate of the present invention can be easily produced and adapted to complex curved surface shapes, and can provide a mirror member with excellent specular properties.

[0012] Fig. 1 is a schematic cross-sectional view of a film mirror laminate according to one embodiment of the present invention, Fig. 2 is a schematic cross-sectional view of a film mirror laminate according to one embodiment of the present invention, Fig. 3 is a schematic cross-sectional view of a mirror member according to one embodiment of the present invention.

[0013] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The following describes in detail the preferred embodiments of the present invention, but the present invention is not limited to the following preferred embodiments.

[0014] [Film mirror laminate] Figure 1 shows a schematic cross-sectional view of a film mirror laminate 1 according to one embodiment of the present invention. The film mirror laminate 1 has a pressure-sensitive adhesive layer 10, a substrate film 11, a metal reflective layer 12, and an optical adjustment layer 13, in this order, and when light is incident on a sample of the film mirror laminate 1 with the pressure-sensitive adhesive layer 10 side attached to a glass plate from the optical adjustment layer 13 side at an incident angle of 60°, the reflection image clarity at an optical comb width of 0.125 mm is 60% or more.

[0015] The film mirror laminate 1 according to an embodiment of the present invention can be used by attaching the surface of the pressure-sensitive adhesive layer 10 opposite to the substrate film 11 to a support substrate. The film mirror laminate 1 according to an embodiment of the present invention is a sample in which the pressure-sensitive adhesive layer side of the film mirror laminate is attached to a glass plate, and light is incident from the optical adjustment layer side at an incident angle of 60°. A measurement of reflection clarity of 60% or more at an optical comb width of 0.125 mm represents the mirror performance of reflection. Therefore, by making the reflection image clarity of 60% or more at an optical comb width of 0.125 mm when light is incident from the optical adjustment layer side at an incident angle of 60°, a film mirror laminate can be obtained that can form a mirror member with excellent specularity.

[0016] The film mirror laminate 1 according to the embodiment of the present invention preferably has a reflection image clarity of 65% or more at an optical comb width of 0.125 mm, more preferably 70% or more, and even more preferably 80% or more.

[0017] Furthermore, when light is incident on the sample from the optical adjustment layer side at an incident angle of 60°, the reflection image clarity at an optical comb width of 0.25 mm is preferably 85% or more, more preferably 90% or more, and even more preferably 95% or more. When light is incident on the sample from the optical adjustment layer side at an incident angle of 60°, the reflection image clarity at an optical comb width of 0.5 mm is preferably 90% or more, more preferably 95% or more, and even more preferably 99% or more. When light is incident on the sample from the optical adjustment layer side at an incident angle of 60°, the reflection image clarity at an optical comb width of 1.0 mm is preferably 90% or more, more preferably 95% or more, and even more preferably 99% or more. When light is incident on the sample from the optical adjustment layer side at an incident angle of 60°, the reflection image clarity at an optical comb width of 2.0 mm is preferably 90% or more, more preferably 95% or more, and even more preferably 99% or more.

[0018] The reflection clarity is measured in accordance with JIS K7374 (Plastics - Determination of Image Clarity) using a sample in which the pressure-sensitive adhesive layer side of the film mirror laminate 1 is attached to a glass plate. The specific measurement procedure and conditions for reflection clarity can be set according to the measurement conditions described in the Examples below, or to obtain results equivalent to or corresponding to those obtained when the measurement conditions are followed. In an embodiment of the present invention, the higher the reflection clarity, the less distortion and higher resolution the image can be projected, and the more likely the specularity will be improved when the film mirror laminate is applied to a mirror member. If the reflection clarity at an optical comb width of 0.125 mm is less than 60%, the specularity will be reduced when the film mirror laminate is applied to a mirror member.

[0019] <Substrate Film> The substrate film 11 is not particularly limited, and may be a film made of a homopolymer or copolymer such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate, polyamide, polyvinyl chloride, polycarbonate (PC), cycloolefin polymer (COP), polystyrene, polypropylene (PP), polyethylene, polycycloolefin, polyurethane, acrylic (PMMA), or ABS. These materials are transparent, have low optical absorption, and do not affect the visual effect. However, since various layers will be formed on the substrate film 11 later, it is preferable that the film be able to withstand high temperatures such as vapor deposition and sputtering. Therefore, among the above materials, for example, polyethylene terephthalate, polyethylene naphthalate, acrylic, polycarbonate, cycloolefin polymer, ABS, polypropylene, and polyurethane are preferred. Among these, polyethylene terephthalate, cycloolefin polymer, polycarbonate, and acrylic are preferred due to their good balance of heat resistance and cost. The substrate film 11 may be a single-layer film or a laminate film. From the viewpoint of ease of processing, the thickness is preferably, for example, about 6 μm to 250 μm. The lower limit of the thickness is more preferably 15 μm or more. The upper limit of the thickness is more preferably 200 μm or less, and even more preferably 150 μm or less. In order to strengthen the adhesive strength with the layer formed on the base film, the base film may be subjected to a plasma treatment or an easy-adhesion treatment.

[0020] The substrate film 11 may optionally have a hard coat layer, such as a smoothness or anti-glare hard coat layer. The provision of a hard coat layer can improve scratch resistance. The hard coat layer can be formed from a hard coat composition. More specifically, the hard coat layer can be formed by applying a solution containing a curable resin as a hard coat composition to the substrate film 11. Examples of the curable resin include thermosetting resins, UV-curable resins, and electron beam-curable resins. Examples of curable resins include polyester-based, acrylic-based, urethane-based, acryl urethane-based, amide-based, silicone-based, silicate-based, epoxy-based, melamine-based, oxetane-based, and acryl urethane-based resins. One or more of these curable resins can be appropriately selected and used. Among these, acrylic resins, acryl urethane-based resins, and epoxy-based resins are preferred due to their high hardness, UV-curability, and excellent productivity.

[0021] The thickness of the hard coat layer is preferably 0.5 μm or more, more preferably 1.0 μm or more, and is preferably 10 μm or less, more preferably 7.0 μm or less, and even more preferably 5.0 μm or less. The thickness of the hard coat layer can be measured, for example, using a film thickness meter (digital dial gauge).

[0022] <Adhesive Layer> As shown in Fig. 3, the film mirror laminate 1 according to an embodiment of the present invention can be used as a mirror member 100, for example, by attaching the surface on the adhesive layer 10 side to a support substrate 21. The adhesive layer 10 can be formed from an adhesive. The adhesive forming the adhesive layer 10 is preferably a transparent adhesive, and for example, any of acrylic adhesives, rubber adhesives, silicone adhesives, polyester adhesives, urethane adhesives, epoxy adhesives, and polyether adhesives can be used alone or in combination of two or more. From the viewpoints of transparency, processability, durability, etc., it is preferable to use an acrylic adhesive.

[0023] The adhesive forming the adhesive layer 10 is preferably formed from an adhesive composition containing a base polymer (hereinafter, sometimes simply referred to as "adhesive composition"). Any known polymer used in adhesives can be used as the base polymer. Here, the base polymer refers to the main component of the polymer contained in the adhesive composition. Furthermore, in this specification, "main component" refers to a component contained in an amount of more than 50% by mass, unless otherwise specified.

[0024] (Pressure-sensitive adhesive composition) The pressure-sensitive adhesive composition preferably contains a (meth)acrylic polymer as a base polymer. Here, (meth)acrylate refers to acrylate and / or methacrylate. Some of the monomers constituting the (meth)acrylic polymer may be contained in the pressure-sensitive adhesive composition as unreacted monomers.

[0025] The (meth)acrylic polymer in the embodiment of the present invention is preferably a hydroxyl group-containing (meth)acrylic polymer containing an alkyl (meth)acrylate and a hydroxyl group-containing monomer as monomer units. The method for introducing the hydroxyl group is not particularly limited, but for example, a method of copolymerizing a hydroxyl group-containing monomer can be easily performed.

[0026] In the embodiments of the present invention, the (meth)acrylic polymer refers to an acrylic polymer and / or a methacrylic polymer, the (meth)acrylate refers to an acrylate and / or a methacrylate, and the alkyl (meth)acrylate refers to an alkyl acrylate and / or an alkyl methacrylate.

[0027] Examples of alkyl (meth)acrylates include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, etc. These compounds may be used alone or in combination of two or more.

[0028] Examples of the hydroxyl group-containing monomer include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, 12-hydroxylauryl (meth)acrylate, (4-hydroxymethylcyclohexyl)methyl acrylate, N-methylol (meth)acrylamide, N-hydroxy (meth)acrylamide, vinyl alcohol, allyl alcohol, 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, diethylene glycol monovinyl ether, etc. These monomers may be used alone or in combination of two or more.

[0029] The hydroxyl group-containing monomers may be used alone or in combination of two or more, but the total content is preferably 1 to 40 parts by mass, and more preferably 2 to 30 parts by mass, per 100 parts by mass of the (meth)acrylic polymer. Copolymerization of the hydroxyl group-containing monomers results in a hydroxyl group-containing (meth)acrylic polymer having reactive sites provided by crosslinking or the like.

[0030] The (meth)acrylic polymer used in the embodiment of the present invention preferably has a weight-average molecular weight of approximately 300,000 to 2,500,000. If the weight-average molecular weight is less than 300,000, the cohesive strength of the pressure-sensitive adhesive composition will be reduced, which tends to cause adhesive residue. The weight-average molecular weight is obtained by measurement using GPC (gel permeation chromatography).

[0031] Furthermore, for the reason that the adhesive properties are easily balanced, it is preferable that the glass transition temperature (Tg) of the (meth)acrylic polymer is 0°C or lower (usually -100°C or higher), preferably -10°C or lower. If the glass transition temperature is higher than 0°C, the polymer becomes less likely to flow. The glass transition temperature (Tg) of the (meth)acrylic polymer can be adjusted to fall within the above range by appropriately changing the monomer components and composition ratios used.

[0032] In addition to the above-mentioned monomers, other polymerizable monomers, such as polymerizable monomers for adjusting the glass transition temperature or releasability of the (meth)acrylic polymer, can be used within a range that does not impair the effects of the present invention.

[0033] Examples of other polymerizable monomers that can be used in the (meth)acrylic polymer include components that improve cohesive strength and heat resistance, such as sulfonic acid group-containing monomers, phosphate group-containing monomers, cyano group-containing monomers, vinyl ester monomers, and aromatic vinyl monomers, and components that improve adhesive strength or have functional groups that act as crosslinking base points, such as acid anhydride group-containing monomers, amide group-containing monomers, amino group-containing monomers, epoxy group-containing monomers, N-acryloylmorpholine, and vinyl ether monomers. These monomer compounds may be used alone or in combination of two or more.

[0034] Examples of the cyano group-containing monomer include acrylonitrile and methacrylonitrile.

[0035] Examples of the vinyl ester monomer include vinyl acetate, vinyl propionate, and vinyl laurate.

[0036] Examples of the aromatic vinyl monomer include styrene, chlorostyrene, chloromethylstyrene, and α-methylstyrene.

[0037] Examples of the amide group-containing monomer include acrylamide, diethylacrylamide, and N-vinyl-2-pyrrolidone.

[0038] Examples of the amino group-containing monomer include N,N-dimethylaminoethyl (meth)acrylate, N,N-dimethylaminopropyl (meth)acrylate, N-(meth)acryloylmorpholine, and (meth)acrylic acid alkylaminoalkyl esters.

[0039] Examples of the epoxy group-containing monomer include glycidyl (meth)acrylate and allyl glycidyl ether.

[0040] Examples of the vinyl ether monomer include methyl vinyl ether, ethyl vinyl ether, and isobutyl vinyl ether.

[0041] In the embodiment of the present invention, the other polymerizable monomers may be used alone or in combination of two or more kinds. However, the total content thereof is preferably 0 to 40 parts by mass, and more preferably 0 to 30 parts by mass, relative to 100 parts by mass of the (meth)acrylic polymer.

[0042] The polymerization method for the (meth)acrylic polymer is not particularly limited, and known polymerization methods such as solution polymerization, emulsion polymerization, suspension polymerization, UV polymerization, etc. The resulting copolymer may be any of a random copolymer, a block copolymer, a graft copolymer, etc.

[0043] In an embodiment of the present invention, the pressure-sensitive adhesive composition may contain a polymer component other than the base polymer.

[0044] In an embodiment of the present invention, the pressure-sensitive adhesive composition preferably contains a crosslinking agent, and the crosslinking agent is preferably an isocyanate-based crosslinking agent, which is used to impart adhesion and cohesion.

[0045] As the isocyanate-based crosslinking agent, a polyfunctional isocyanate compound is used, and includes various compounds having two or more isocyanate groups in the molecule.

[0046] Examples of the isocyanate compound include lower aliphatic polyisocyanates such as butylene diisocyanate and hexamethylene diisocyanate; alicyclic isocyanates such as cyclopentylene diisocyanate, cyclohexylene diisocyanate and isophorone diisocyanate; aromatic isocyanates such as 2,4-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate and xylylene diisocyanate; and isocyanate adducts such as trimethylolpropane / tolylene diisocyanate trimer adduct (trade name: Coronate L, manufactured by Nippon Polyurethane Industry Co., Ltd.), trimethylolpropane / hexamethylene diisocyanate trimer adduct (trade name: Coronate HL, manufactured by Nippon Polyurethane Industry Co., Ltd.), and hexamethylene diisocyanate isocyanurate (trade name: Coronate HX, manufactured by Nippon Polyurethane Industry Co., Ltd.). Among these, those having an isocyanurate ring are particularly preferred, and examples thereof include a polyisocyanate having a long-chain alkylene diol-modified isocyanurate ring (Burnoc DN-995, manufactured by Dainippon Ink and Chemicals, Inc.), an isocyanurate of hexamethylene diisocyanate (trade name: Coronate HX, manufactured by Nippon Polyurethane Industry Co., Ltd.), etc. These compounds may be used alone or in combination.

[0047] The content of the crosslinking agent used in the embodiment of the present invention may be such that it does not affect the adhesive properties, but it is usually contained in an amount of 0.2 to 10 parts by mass, preferably 0.5 to 8 parts by mass, and more preferably 1 to 6 parts by mass, relative to 100 parts by mass of the (meth)acrylic polymer.

[0048] In an embodiment of the present invention, the PSA composition also preferably contains a polyfunctional (meth)acrylic monomer such as 1,6-hexanediol diacrylate as a crosslinking component. The (meth)acrylic monomer in the embodiment of the present invention refers to an acrylic monomer and / or a methacrylic monomer. The polyfunctional (meth)acrylic monomer is typically contained in an amount of 0.2 to 10 parts by mass, preferably 0.5 to 8 parts by mass, and more preferably 1 to 6 parts by mass, per 100 parts by mass of the (meth)acrylic polymer.

[0049] In addition to the above-mentioned examples, the acrylic pressure-sensitive adhesive may also contain appropriate crosslinking agents (polyamine compounds, melamine resins, aziridine derivatives, urea resins), polymerization initiators, tackifiers, plasticizers, silane coupling agents, colorants, powders such as pigments, dyes, surfactants, surface lubricants, leveling agents, softeners, antioxidants, antistatic agents, antiaging agents, light stabilizers, ultraviolet absorbers, polymerization inhibitors, inorganic or organic fillers, metal powders, particulate or foil-like materials, etc. These components may be used alone or in combination of two or more.

[0050] (Adhesion strength of pressure-sensitive adhesive layer) In the film mirror laminate according to the embodiment of the present invention, from the viewpoint of preventing peeling at the interface between the substrate film and the pressure-sensitive adhesive layer, the adhesive strength of the pressure-sensitive adhesive layer to the substrate film is preferably 5 N / 25 mm or more, more preferably 10 N / 25 mm or more, and even more preferably 15 N / 25 mm or more. Also, it is preferably 40 N / 25 mm or less, more preferably 35 N / 25 mm or less, and even more preferably 30 N / 25 mm or less. Furthermore, in the film mirror laminate according to the embodiment of the present invention, from the viewpoint of preventing peeling at the interface between the pressure-sensitive adhesive layer and the substrate when the surface of the pressure-sensitive adhesive layer side of the film mirror laminate is attached to the substrate, the adhesive strength of the pressure-sensitive adhesive layer to the substrate is preferably 5 N / 25 mm or more, more preferably 10 N / 25 mm or more, and even more preferably 15 N / 25 mm or more. Furthermore, from the viewpoint of reworkability (the process of peeling off and re-attaching if there is a problem with the attachment), the strength is preferably 40 N / 25 mm or less, more preferably 35 N / 25 mm or less, and even more preferably 30 N / 25 mm or less.

[0051] (Method of forming pressure-sensitive adhesive layer) The pressure-sensitive adhesive layer can also be formed, for example, by applying the pressure-sensitive adhesive composition to a base film and then drying and removing the solvent, etc. When applying the pressure-sensitive adhesive composition, one or more solvents may be added as appropriate. Alternatively, the pressure-sensitive adhesive layer can also be formed, for example, by laminating the surface of the pressure-sensitive adhesive layer formed on a release liner using the pressure-sensitive adhesive composition and the release liner to a base film.

[0052] The thickness of the pressure-sensitive adhesive layer is preferably 10 to 70 μm, more preferably 15 to 65 μm, even more preferably 15 to 60 μm, and even more preferably 20 to 55 μm. The thickness of the pressure-sensitive adhesive layer can be measured with a dial gauge.

[0053] Various methods can be used to apply the pressure-sensitive adhesive composition, specifically, for example, roll coating, kiss roll coating, gravure coating, reverse coating, roll brushing, spray coating, dip roll coating, bar coating, knife coating, air knife coating, curtain coating, lip coating, extrusion coating using a die coater, etc.

[0054] The heating and drying temperature is preferably about 30°C to 200°C, more preferably 40°C to 180°C, and even more preferably 80°C to 160°C. By setting the heating temperature within the above range, a pressure-sensitive adhesive layer having excellent adhesive properties can be obtained. An appropriate drying time can be adopted as needed. The drying time is preferably about 5 seconds to 20 minutes, more preferably 30 seconds to 10 minutes, and even more preferably 1 minute to 8 minutes.

[0055] When the pressure-sensitive adhesive composition is an active energy ray-curable pressure-sensitive adhesive, the pressure-sensitive adhesive layer can be formed by irradiating the composition with active energy rays such as ultraviolet rays. For ultraviolet irradiation, a high-pressure mercury lamp, a low-pressure mercury lamp, a metal halide lamp, a chemical light lamp, or the like can be used.

[0056] It is preferable that the pressure-sensitive adhesive layer 10 is protected by a release liner until it is attached to an adherend. For example, when the film mirror laminate is shipped, the pressure-sensitive adhesive layer is protected by a release liner, and then the release liner is peeled off and the film mirror laminate is laminated with a supporting substrate to produce a mirror member.

[0057] The release liner is not particularly limited as long as it can protect the pressure-sensitive adhesive layer, and examples thereof include suitable thin sheets such as porous materials such as plastic film, paper, cloth, and nonwoven fabric, net, foam sheet, metal foil, and laminates thereof, but plastic film is preferably used because of its excellent surface smoothness.

[0058] Examples of the plastic film include polyethylene film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, polyvinyl chloride film, vinyl chloride copolymer film, polyethylene terephthalate film, polybutylene terephthalate film, polyurethane film, and ethylene-vinyl acetate copolymer film.

[0059] The thickness of the release liner is usually 5 to 200 μm, preferably 5 to 100 μm. If necessary, the release liner can be subjected to a release and antifouling treatment using a silicone-based, fluorine-based, long-chain alkyl-based or fatty acid amide-based release agent, silica powder, or the like, or an antistatic treatment such as a coating type, kneading type, or vapor deposition type. In particular, by appropriately subjecting the surface of the release liner to a release treatment such as silicone treatment, long-chain alkyl treatment, or fluorine treatment, the releasability from the pressure-sensitive adhesive layer can be further improved.

[0060] From the viewpoint of obtaining a mirror member having an excellent specularity, it is preferable that the surface of the release liner that comes into contact with the pressure-sensitive adhesive layer has high smoothness. For example, the surface of the release liner that comes into contact with the pressure-sensitive adhesive layer preferably has a maximum roughness in height Rz of 1000 μm or less, more preferably 900 μm or less, and even more preferably 800 μm or less. By setting the maximum roughness in height Rz within the above range for the surface of the release liner that comes into contact with the pressure-sensitive adhesive layer, the surface of the pressure-sensitive adhesive layer becomes smooth, and a film mirror laminate that can form a mirror member having an excellent specularity can be obtained.

[0061] The maximum height roughness Rz of the surface of the release liner can be measured using a non-contact surface roughness measuring device. An optical interference type surface roughness measuring device, such as the Wyko NT-9100 manufactured by Veeco or an equivalent, can be used as the non-contact surface roughness measuring device. Specific measurement procedures and conditions can be set according to the measurement conditions described in the Examples below, or to obtain results equivalent to or corresponding to those obtained when the measurement conditions are followed.

[0062] <Metallic Reflective Layer> The metallic reflective layer 12 in this embodiment is formed on the substrate film 11. The metallic reflective layer 12 is preferably a layer having metallic luster. There are no particular limitations on the material forming the metallic reflective layer 12, and it may contain a metal and a resin. The metallic reflective layer 12 may be a metal layer. A case where the metallic reflective layer 12 is a metal layer will be described.

[0063] The metal reflective layer 12 desirably has a relatively low melting point as well as sufficient brilliance. This is because the metal reflective layer 12 is preferably formed by thin-film growth using sputtering. For these reasons, a metal with a melting point of approximately 1000°C or less is suitable for the metal reflective layer 12, and it is preferable that the metal reflective layer 12 contains at least one metal selected from aluminum (Al), zinc (Zn), lead (Pb), copper (Cu), and silver (Ag), or an alloy containing such a metal as a main component. In particular, aluminum or an aluminum alloy is preferably used for reasons of the brilliance, stability, cost, etc. of the material. Furthermore, when an aluminum alloy is used, it is preferable that the aluminum content be 50% by mass or more.

[0064] The thickness of the metal reflective layer 12 is preferably 20 nm or more to ensure sufficient brilliance, but is preferably 100 nm or less from the viewpoints of sheet resistance and electromagnetic wave transmittance. For example, 20 nm to 100 nm is preferred, and 30 nm to 70 nm is more preferred. This thickness is suitable for forming a uniform film with good productivity, and also provides a good appearance when a mirror member produced by attaching the film mirror laminate 1 to a support substrate is used as a mirror surface.

[0065] <Optical Adjustment Layer> The film mirror laminate 1 according to an embodiment of the present invention includes an optical adjustment layer 13 on the surface of the metal reflective layer 12 opposite the substrate film 11. By including the optical adjustment layer 13, the film mirror laminate 1 according to an embodiment of the present invention has a neutral hue of reflected light, allowing images from a light source to be projected without color change. The optical adjustment layer 13 according to an embodiment of the present invention preferably includes at least one high refractive index layer having a refractive index of 1.75 or more. By including the high refractive index layer as the optical adjustment layer, the reflection spectrum can be adjusted and the reflectance in the visible light region can be increased. In this specification, unless otherwise specified, "refractive index" refers to a value measured in accordance with JIS K0062:1992 using light with a wavelength λ of 550 nm at a temperature of 25°C.

[0066] (High Refractive Index Layer) The high refractive index layer preferably included in the optical adjustment layer according to the embodiment of the present invention is a layer having a refractive index of 1.75 or more, more preferably 1.75 to 3.2, and even more preferably 1.80 to 2.40. When a plurality of high refractive index layers are provided, the refractive indices of the high refractive index layers may be the same or different.

[0067] The high refractive index layer is preferably a layer made of a metal oxide and / or a metal nitride. The metal elements contained in the metal oxides and metal nitrides referred to here include metalloid elements such as Si. The metal oxides and / or metal nitrides include metal oxynitrides. The metal oxides may be oxides of a single metal element (single oxides) or oxides of multiple metal elements (complex oxides). Similarly, the metal nitrides may be nitrides of a single metal element (single nitrides) or nitrides of multiple metal elements (complex nitrides). Examples of metal elements include Ce, Nb, Si, Sb, Ti, Ta, Zr, and Zn.

[0068] More specifically, the material of the high refractive index layer is, for example, CeO ２ (2.30), NbO (2.33), Nb ２ O ３ (2.15), Nb ２ O ５ (2.32), SiN (2.03), Sb ２ O ３ (2.10), TiO ２ (2.35), Ta ２ O ５ (2.10), ZrO ２ (2.05), ZnO (2.10), ZnS (2.30), tin-doped indium oxide (ITO), antimony-doped tin oxide (ATO), etc. (The numbers in parentheses for each of the above materials are refractive indices.) In particular, the high refractive index layer preferably contains at least one selected from Nb, Si, and Ti, for example, NbO ｘ , SiN ｘ , TiO ｘ It is preferable that the material contains at least one selected from the group consisting of NbO ｘ It is more preferable that the alloy contains niobium oxide.

[0069] The thickness of the high refractive index layer 13b is preferably 10 nm or more, more preferably 20 nm or more, and even more preferably 30 nm or more, from the viewpoint of improving the reflectance in the visible light region, and is preferably 100 nm or less, more preferably 80 nm or less, and even more preferably 70 nm or less, from the viewpoint of improving the reflectance in the visible light region.

[0070] The optical adjustment layer may be a laminate of layers having different refractive indices, and may include a low refractive index layer in addition to a high refractive index layer. As shown in Figure 2, the film mirror laminate 1 according to the embodiment of the present invention has a pressure-sensitive adhesive layer 10, a base film 11, a metal reflective layer 12, and an optical adjustment layer 13 in this order, and the optical adjustment layer 13 may be a laminate of a first low refractive index layer 13a, a high refractive index layer 13b, and a second low refractive index layer 13c.

[0071] (Low Refractive Index Layer) The low refractive index layer is a layer having a refractive index lower than that of the high refractive index layer, and its refractive index is, for example, 1.35 to 1.55, preferably 1.40 to 1.50. One or more low refractive index layers may be provided, and when more than one low refractive index layer is provided, the refractive indices of the low refractive index layers may be the same or different. For example, the optical adjustment layer may include two low refractive index layers, a first low refractive index layer and a second low refractive index layer, and the refractive index of the first low refractive index layer may be the same as or different from that of the second low refractive index layer.

[0072] Examples of materials for the low refractive index layer include metal oxides and metal fluorides. The metal elements contained in the metal oxides and metal fluorides referred to here include metalloid elements such as Si. Metal oxides and / or metal fluorides include metal oxyfluorides. The metal oxide may be an oxide of a single metal element (single oxide) or an oxide of multiple metal elements (complex oxide). Similarly, the metal fluoride may be a fluoride of a single metal element (single fluoride) or a fluoride of multiple metal elements (complex fluoride). Examples of metal elements include Si and Mg.

[0073] Specific examples of metal oxides include silicon oxide (SiO ２ : refractive index 1.46). Specific examples of metal fluorides include magnesium fluoride and fluorosilicic acid. As the material for the first low refractive index layer and the second low refractive index layer, magnesium fluoride and fluorosilicic acid are preferred from the viewpoint of refractive index, and silicon oxide is preferred from the viewpoints of ease of production, mechanical strength, moisture resistance, etc., with silicon oxide being preferred when various properties are taken into consideration comprehensively. When a plurality of low refractive index layers are provided, the materials for the low refractive index layers may be the same or different, but it is preferable that all of the low refractive index layers contain silicon oxide.

[0074] The thickness of the first low refractive index layer 13a is preferably 10 nm or more, more preferably 20 nm or more, and even more preferably 30 nm or more, from the viewpoint of improving the reflectance in the visible light region, and is preferably 200 nm or less, more preferably 150 nm or less, and even more preferably 100 nm or less, from the viewpoint of improving the reflectance in the visible light region.

[0075] From the viewpoint of improving reflectance in the visible light region, the thickness of the second low refractive index layer 13c is preferably 5 nm or more, more preferably 10 nm or more, and is preferably 50 nm or less, more preferably 30 nm or less, and even more preferably 20 nm or less.

[0076] In the film mirror laminate according to an embodiment of the present invention, the optical adjustment layer may include a low refractive index layer and a high refractive index layer. Furthermore, the film mirror laminate 1 may further include a layer made of, for example, titanium oxide or a mixture of the above-mentioned low refractive index material and a high refractive index material (such as a mixture of titanium oxide and silicon oxide) as a medium refractive index layer having a refractive index of approximately 1.50 to 1.85. Examples of the optical adjustment layer include, from the metal reflective layer 12 side, the above-mentioned three-layer structure of a first low refractive index layer, a high refractive index layer, and a second low refractive index layer; a four-layer structure of a high refractive index layer, a first low refractive index layer, a high refractive index layer, and a second low refractive index layer; and a five-layer structure of a first low refractive index layer, a high refractive index layer, a medium refractive index layer, a high refractive index layer, and a second low refractive index layer. The optical adjustment layer may also be a laminate of six or more thin films.

[0077] The film mirror laminate 1 may have a plurality of optical adjustment layers 13. For example, some oxides, such as niobium oxide, are reduced when exposed to ultraviolet light while laminated with a pressure-sensitive adhesive, and a silicon oxide layer may be further laminated as a protective layer to prevent the reduction reaction.

[0078] The film mirror laminate according to the embodiment of the present invention may include, in addition to the pressure-sensitive adhesive layer, the substrate film, the metal reflective layer, and the optical adjustment layer, other layers depending on the intended use. Examples of the other layers include a surface protective coating layer, a clear hard coating layer, an easy-adhesion layer, an anti-reflection layer, a light extraction layer, and an anti-glare layer.

[0079] [Manufacturing of Film Mirror Laminate] The manufacturing method of the film mirror laminate according to the embodiment of the present invention is not particularly limited. For example, a metal reflective layer 12 can be formed on one surface of a substrate film 11, and an optical adjustment layer 13 can be formed on the metal reflective layer 12. The pressure-sensitive adhesive layer 10 can be formed directly on the other surface of the substrate film 11 by coating a composition capable of forming the pressure-sensitive adhesive layer 10, or by laminating a separately formed pressure-sensitive adhesive layer 10.

[0080] The method for forming the metal reflective layer 12 and the optical adjustment layer 13 is not particularly limited, and examples thereof include vacuum deposition, sputtering, ion plating, etc. Sputtering is preferred because it allows strict control of the thickness even over a large area.

[0081] The film mirror laminate according to the embodiment of the present invention can be used for a mirror member. The film mirror laminate according to the embodiment can also be used for decorating a member. For example, it can be attached to a member to be adhered, and the member to be adhered can be, for example, a member made of glass or plastic, but is not limited thereto.

[0082] [Mirror member] A mirror member according to an embodiment of the present invention comprises the above-mentioned film mirror laminate and a supporting substrate, and the surface of the film mirror laminate facing the pressure-sensitive adhesive layer is attached to the supporting substrate. Figure 3 is a schematic cross-sectional view of a mirror member according to an embodiment of the present invention. The mirror member 100 shown in Figure 3 is a film mirror laminate having a pressure-sensitive adhesive layer 10, a substrate film 11, a metal reflective layer 12, and an optical adjustment layer 13 in this order, with the surface facing the pressure-sensitive adhesive layer 10 attached to a supporting substrate 21. When a sample of the film mirror laminate with the surface facing the pressure-sensitive adhesive layer attached to a glass plate is irradiated with light at an incident angle of 60° from the optical adjustment layer side, the reflection image clarity at an optical comb width of 0.125 mm is 60% or more.

[0083] [Manufacturing of Mirror Member] The manufacturing method of the mirror member according to this embodiment is not particularly limited, but the mirror member may be a mirror member in which the above-mentioned film mirror laminate and the supporting substrate of the mirror member are laminated by film insert molding. The mirror member may also be a mirror member in which the above-mentioned film mirror laminate and the supporting substrate of the mirror member are laminated by lamination. The manufacturing method of the mirror member will be described below.

[0084] In the mirror member according to the embodiment of the present invention, since the film mirror laminate is in the form of a film, it can be attached to a supporting substrate and can be produced with good productivity.

[0085] (Support Substrate) The material for the support substrate of the mirror member according to one embodiment of the present invention is not particularly limited, and examples thereof include resin, glass, metal, etc. Resin is preferably used from the viewpoint of processability and moisture content of the support substrate. Examples of resins include polyester resins such as polyethylene terephthalate (PET), polybutylene terephthalate, and polyethylene naphthalate; (meth)acrylic resins (acrylic resins and / or methacrylic resins) such as polymethacrylate; olefin resins such as polyethylene, polypropylene, and cycloolefin polymers (e.g., norbornene-based, cyclopentadiene-based); and polycarbonate resins, polyethersulfone resins, polyarylate resins, melamine resins, polyamide resins, polyimide resins, cellulose resins, and polystyrene resins. These materials can be used alone or in combination of two or more. Among these, polycarbonate resins are preferred from the viewpoint of processability and heat resistance.

[0086] [Uses of Film Mirror Laminate and Mirror Member] Examples of uses of the film mirror laminate and mirror member of this embodiment include vehicle structural parts, vehicle-mounted accessories such as head-up displays, housings for electronic devices, housings for home appliances, structural parts, machine parts, various automobile parts, electronic device parts, household goods applications such as furniture and kitchenware, medical equipment, building material parts, other structural parts and exterior parts, etc. More specifically, in the vehicle-related field, examples include instrument panels, console boxes, door handles, door trim, shift levers, pedals, glove boxes, bumpers, hoods, fenders, trunks, doors, roofs, pillars, seats, steering wheels, ECU boxes, electrical parts, engine peripheral parts, drive system / gear peripheral parts, intake / exhaust system parts, cooling system parts, etc. More specific examples of electronic devices and home appliances include home appliances such as refrigerators, washing machines, vacuum cleaners, microwave ovens, air conditioners, lighting equipment, electric water heaters, televisions, clocks, ventilation fans, projectors, and speakers, as well as electronic information devices such as personal computers, mobile phones, smartphones, digital cameras, tablet PCs, portable music players, portable game consoles, chargers, and batteries. Among the above, the material can be particularly suitably used as a mirror member for a head-up display.

[0087] The present invention will be described below based on examples, but the present invention is not limited to these examples.

[0088] <Production of film mirror laminate and mirror member> [Production of metal reflective layer] A PET film mirror (hereinafter referred to as film substrate) manufactured by Toray Industries, Inc. was prepared as a substrate film. An Al target was set in a magnetron sputtering device, and an aluminum layer (Al layer) having a thickness of 44 nm was formed as a metal reflective layer on one side of the film substrate.

[0089] (Al layer formation conditions) Ultimate vacuum: 1.0×10 －４ Pa Sputtering gas: Ar Chamber pressure: 0.30 Pa Substrate temperature: 25°C

[0090] [Preparation of Optical Adjustment Layer] The film substrate on which the Al layer was formed was set in a magnetron sputtering device, and silicon oxide 67 nm (refractive index 1.46), niobium oxide (Nb ２ O ５ ) 53 nm (refractive index 2.32), silicon oxide (SiO ２ ) 20 nm thick, and then a thin film of a transparent oxide was formed as an optical adjustment layer. In forming the thin films of silicon oxide and niobium oxide, a pure silicon target and a pure niobium target were used as targets, and oxygen gas was introduced in addition to argon gas to perform reactive sputtering, thereby obtaining the thin films of the respective transparent oxides.

[0091] (Silicon oxide film formation conditions) Ultimate vacuum: 1.0×10 －４ Pa sputtering gas: Ar and O ２ Using O ２ / (Ar + O ２ ) adjusted to 0.3 Chamber pressure: 0.30 Pa Substrate temperature: 25°C

[0092] (Niobium oxide film formation conditions) Ultimate vacuum: 1.0×10 －４ Pa sputtering gas: Ar and O ２ Using O ２ / (Ar + O ２ ) adjusted to 0.1 Chamber pressure: 0.30 Pa Substrate temperature: 25°C

[0093] As a result, Laminate 1 was produced, in which thin layers of aluminum 44 nm, silicon oxide 67 nm, niobium oxide 53 nm, and silicon oxide 20 nm were formed in this order on one side of a 50 μm PET substrate.

[0094] Example 1 A film mirror laminate was produced by peeling off the light-release liner (Rz on the adhesive layer side: 759 μm) of a 25 μm-thick adhesive sheet (CS9861F, manufactured by Nitto Denko Corporation) used as an adhesive layer and bonding it to the side of the substrate film of Laminate 1 that had not been sputter-deposited. The heavy-release liner on the adhesive layer side of the film mirror laminate (Rz on the adhesive layer side: 833 μm) was peeled off and the film mirror laminate was bonded to a 1.2-1.5 mm-thick glass plate (S200200, manufactured by Matsunami Glass Industrial Co., Ltd.) used as a supporting substrate, producing a mirror member. The test piece size was 50 mm × 150 mm.

[0095] Comparative Example 1 A film mirror laminate and a mirror member were produced in the same manner as in Example 1, except that the adhesive sheet was changed to an adhesive sheet (CS9861UAS, manufactured by Nitto Denko Corporation) having an Rz of 1196 μm on the adhesive layer side of the light release liner, an Rz of 1044 μm on the adhesive layer side of the heavy release liner, and a thickness of 25 μm.

[0096] <60° Reflection Image Clarity (%)> The film mirror laminates prepared in the Examples and Comparative Examples were each attached to a glass plate with the pressure-sensitive adhesive layer 10 side. According to JIS K7374 (Plastics - Determination of Image Clarity), 60° reflection image clarity was measured using an image clarity measuring instrument ICM-1T (manufactured by Suga Test Instruments Co., Ltd.) under optical conditions of an incident angle of 60° and an acceptance angle of 60°. Light from the light source was passed through a light source slit with a width of 0.03 mm and converted into parallel light using a lens. The light source image was irradiated from the optical adjustment layer 13 side of the sample, and the reflected image was formed on an optical comb and received by a photoreceiver for measurement. The optical comb has a width ratio of 1:1 between the light-shielding part and the light-transmitting part (slit), and the slit widths are arranged in order as 0.125 mm, 0.25 mm, 0.5 mm, 1.0 mm, and 2.0 mm (optical comb width (optical comb mesh width) 0.125 mm, 0.25 mm, 0.5 mm, 1.0 mm, and 2.0 mm). The slit width moves continuously from the widest part to the narrowest part until it reaches the dark part, and the image is repeatedly transmitted and shielded. The largest value of the received light amount obtained by the light receiver is called the maximum received light amount M ｎ , the smallest value is the minimum light receiving amount m ｎ The image clarity (image clarity) C is calculated by the following formula (1): ｎ(%) was calculated and used as the 60° reflection image clarity.

[0097]

[0098] <Rz of Release Liner> The maximum height roughness Rz (μm) of the surface of the release liner used in Examples and Comparative Examples that contacts the pressure-sensitive adhesive layer was measured. The measurement was performed using a scanning white light interferometer "Zygo NewView7300" (manufactured by ZYGO Corporation) under the following conditions. [Measurement conditions] Objective lens: 10x Zoom lens: 1x Remove: Cylinder

[0099] <Unevenness Evaluation> The unevenness numerical value was measured for the mirror members produced in the examples and comparative examples. First, the produced mirror member was used as an evaluation sample, and the optical adjustment layer side of the mirror member was facing the light source, and the angle with respect to the light beam from the light source was approximately 45 degrees. A white screen was placed at the end of the light beam, and the reflected image was projected onto it. The light source used was a "Mercury Xenon Lamp" manufactured by Hamamatsu Photonics K.K. The light source, evaluation sample, and screen were positioned so that the distance between the evaluation sample and the light source, and the distance between the evaluation sample and the screen, were each approximately 50 cm. The unevenness numerical value was measured by turning on the light source, photographing the reflected image reflected by the sample and projected onto the screen with an EyeScale-4W camera, and reading the photographed image in ISC-S mode. A value of 20 or less was considered good.

[0100] The measurement results and evaluation results for each of the Examples and Comparative Examples are shown in Table 1 below.

[0101]

[0102] As described above, the mirror member using the film mirror laminate of this example had a 60° reflection image clarity of 60% or more on a 0.125 mm wide optical comb, so the unevenness value was low and the mirror surface was excellent, so the film mirror laminate of this example was suitable for mirror members. In addition, the film mirror laminate of this example can be attached to a supporting substrate via an adhesive layer, allowing for the production of mirror members with high productivity and easy adaptation to complex curved surface shapes, etc.

[0103] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention.

[0104] The film mirror laminate of the present invention can provide a mirror member with excellent specularity, and can be easily adapted to complex curved surface shapes with good productivity, and can provide a mirror member with excellent specularity.

[0105] Although the present invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the present invention. This application is based on a Japanese patent application (Patent Application No. 2023-100167) filed on June 19, 2023, the contents of which are incorporated herein by reference.

[0106] REFERENCE SIGNS LIST 1 film mirror laminate 10 pressure-sensitive adhesive layer 11 substrate film 12 metal reflective layer 13 optical adjustment layer 13a first low refractive index layer 13b high refractive index layer 13c second low refractive index layer 21 supporting substrate 100 mirror member

Claims

1. A film mirror laminate having an adhesive layer, a base film, a metal reflective layer, and an optical adjustment layer in that order, wherein a sample of the film mirror laminate in which the adhesive layer side is attached to a glass plate has a reflection image clarity of 60% or more at an optical comb width of 0.125 mm when light is incident from the optical adjustment layer side at an incident angle of 60°.

2. The film mirror laminate according to claim 1, wherein the optical adjustment layer comprises a low refractive index layer and a high refractive index layer.

3. The film mirror laminate according to claim 2, wherein the low refractive index layer contains silicon oxide.

4. The film mirror laminate according to claim 2, wherein the high refractive index layer contains niobium oxide.

5. The film mirror laminate according to claim 1, wherein the metal reflective layer contains at least one metal selected from aluminum (Al), zinc (Zn), lead (Pb), copper (Cu), and silver (Ag), or an alloy containing the metal as a main component.

6. A mirror member comprising the film mirror laminate according to any one of claims 1 to 5 and a supporting substrate, the surface of the film mirror laminate facing the adhesive layer being attached to the supporting substrate.

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